<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: ZhangXuehun <zhangxuehun@sohu.com>
// +----------------------------------------------------------------------
// $Id: DbOracle.class.php 2729 2012-02-12 04:13:34Z liu21st $


/**
+------------------------------
 * Oracle数据库驱动类
+------------------------------
 */
class DbOracle extends Db {
	
	private $mode = OCI_COMMIT_ON_SUCCESS;
	private $table = '';
	protected $selectSql = 'SELECT * FROM (SELECT thinkphp.*, rownum AS numrow FROM (SELECT  %DISTINCT% %FIELD% FROM %TABLE%%JOIN%%WHERE%%GROUP%%HAVING%%ORDER%) thinkphp ) %LIMIT%';
	
	/**
     +----------------------------------------------------------
	 * 架构函数 读取数据库配置信息
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param array $config 数据库配置数组
     +----------------------------------------------------------
	 */
	public function __construct($config = '') {
		putenv ( "NLS_LANG=AMERICAN_AMERICA.UTF8" );
		if (! extension_loaded ( 'oci8' )) {
			throw_exception ( L ( '_NOT_SUPPERT_' ) . 'oracle' );
		}
		if (! empty ( $config )) {
			$this->config = $config;
			if (empty ( $this->config ['params'] )) {
				$this->config ['params'] = array ();
			}
		}
	}
	
	/**
     +----------------------------------------------------------
	 * 连接数据库方法
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function connect($config = '', $linkNum = 0) {
		if (! isset ( $this->linkID [$linkNum] )) {
			if (empty ( $config ))
				$config = $this->config;
			$pconnect = ! empty ( $config ['params'] ['persist'] ) ? $config ['params'] ['persist'] : $this->pconnect;
			$conn = $pconnect ? 'oci_pconnect' : 'oci_new_connect';
			$this->linkID [$linkNum] = $conn ( $config ['username'], $config ['password'], $config ['database'] ); //modify by wyfeng at 2008.12.19
			

			if (! $this->linkID [$linkNum]) {
				$error = $this->error ( false );
				throw_exception ( $error ["message"], '', $error ["code"] );
			}
			// 标记连接成功
			$this->connected = true;
			//注销数据库安全信息
			if (1 != C ( 'DB_DEPLOY_TYPE' ))
				unset ( $this->config );
		}
		return $this->linkID [$linkNum];
	}
	
	/**
     +----------------------------------------------------------
	 * 释放查询结果
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 */
	public function free() {
		oci_free_statement ( $this->queryID );
		$this->queryID = null;
	}
	
	/**
     +----------------------------------------------------------
	 * 执行查询 返回数据集
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $str  sql指令
     +----------------------------------------------------------
	 * @return mixed
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function query($str) {
		$this->initConnect ( false );
		if (! $this->_linkID)
			return false;
		$this->queryStr = $str;
		//更改事务模式
		$this->mode = OCI_COMMIT_ON_SUCCESS;
		//释放前次的查询结果
		if ($this->queryID)
			$this->free ();
		N ( 'db_query', 1 );
		// 记录开始执行时间
		G ( 'queryStartTime' );
		$this->queryID = oci_parse ( $this->_linkID, $str );
		$this->debug ();
		if (false === oci_execute ( $this->queryID, $this->mode )) {
			$this->error ();
			return false;
		} else {
			return $this->getAll ();
		}
	}
	
	/**
     +----------------------------------------------------------
	 * 执行语句
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $str  sql指令
     +----------------------------------------------------------
	 * @return integer
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function execute($str) {
		$this->initConnect ( true );
		if (! $this->_linkID)
			return false;
		$this->queryStr = $str;
		// 判断新增操作
		$flag = false;
		if (preg_match ( "/^\s*(INSERT\s+INTO)\s+(\w+)\s+/i", $this->queryStr, $match )) {
			$this->table = C ( "DB_SEQUENCE_PREFIX" ) . str_ireplace ( C ( "DB_PREFIX" ), "", $match [2] );
			$flag = ( boolean ) $this->query ( "SELECT * FROM user_sequences WHERE sequence_name='" . strtoupper ( $this->table ) . "'" );
		} //modify by wyfeng at 2009.08.28
		

		//更改事务模式
		$this->mode = OCI_COMMIT_ON_SUCCESS;
		//释放前次的查询结果
		if ($this->queryID)
			$this->free ();
		N ( 'db_write', 1 );
		// 记录开始执行时间
		G ( 'queryStartTime' );
		$stmt = oci_parse ( $this->_linkID, $str );
		$this->debug ();
		if (false === oci_execute ( $stmt )) {
			$this->error ();
			return false;
		} else {
			$this->numRows = oci_num_rows ( $stmt );
			$this->lastInsID = $flag ? $this->insertLastId () : 0; //modify by wyfeng at 2009.08.28
			return $this->numRows;
		}
	}
	
	/**
     +----------------------------------------------------------
	 * 启动事务
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return void
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function startTrans() {
		$this->initConnect ( true );
		if (! $this->_linkID)
			return false;
		
		//数据rollback 支持
		if ($this->transTimes == 0) {
			$this->mode = OCI_DEFAULT;
		}
		$this->transTimes ++;
		return;
	}
	
	/**
     +----------------------------------------------------------
	 * 用于非自动提交状态下面的查询提交
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function commit() {
		if ($this->transTimes > 0) {
			$result = oci_commit ( $this->_linkID );
			if (! $result) {
				throw_exception ( $this->error () );
			}
			$this->transTimes = 0;
		}
		return true;
	}
	
	/**
     +----------------------------------------------------------
	 * 事务回滚
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function rollback() {
		if ($this->transTimes > 0) {
			$result = oci_rollback ( $this->_linkID );
			if (! $result) {
				throw_exception ( $this->error () );
			}
			$this->transTimes = 0;
		}
		return true;
	}
	
	/**
     +----------------------------------------------------------
	 * 获得所有的查询数据
     +----------------------------------------------------------
	 * @access private
     +----------------------------------------------------------
	 * @return array
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	private function getAll() {
		//返回数据集
		$result = array ();
		$this->numRows = oci_fetch_all ( $this->queryID, $result, 0, - 1, OCI_FETCHSTATEMENT_BY_ROW );
		//add by wyfeng at 2008-12-23 强制将字段名转换为小写，以配合Model类函数如count等
		if (C ( "DB_CASE_LOWER" )) {
			foreach ( $result as $k => $v ) {
				$result [$k] = array_change_key_case ( $result [$k], CASE_LOWER );
			}
		}
		return $result;
	}
	
	/**
     +----------------------------------------------------------
	 * 取得数据表的字段信息
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function getFields($tableName) {
		$result = $this->query ( "select a.column_name,data_type,decode(nullable,'Y',0,1) notnull,data_default,decode(a.column_name,b.column_name,1,0) pk " . "from user_tab_columns a,(select column_name from user_constraints c,user_cons_columns col " . "where c.constraint_name=col.constraint_name and c.constraint_type='P'and c.table_name='" . strtoupper ( $tableName ) . "') b where table_name='" . strtoupper ( $tableName ) . "' and a.column_name=b.column_name(+)" );
		$info = array ();
		if ($result) {
			foreach ( $result as $key => $val ) {
				$info [strtolower ( $val ['column_name'] )] = array ('name' => strtolower ( $val ['column_name'] ), 'type' => strtolower ( $val ['data_type'] ), 'notnull' => $val ['notnull'], 'default' => $val ['data_default'], 'primary' => $val ['pk'], 'autoinc' => $val ['pk'] );
			}
		}
		return $info;
	}
	
	/**
     +----------------------------------------------------------
	 * 取得数据库的表信息（暂时实现取得用户表信息）
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function getTables($dbName = '') {
		$result = $this->query ( "select table_name from user_tables" );
		$info = array ();
		foreach ( $result as $key => $val ) {
			$info [$key] = current ( $val );
		}
		return $info;
	}
	
	/**
     +----------------------------------------------------------
	 * 关闭数据库
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 */
	public function close() {
		if ($this->_linkID) {
			oci_close ( $this->_linkID );
		}
		$this->_linkID = null;
	}
	
	/**
     +----------------------------------------------------------
	 * 数据库错误信息
	 * 并显示当前的SQL语句
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return string
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function error($result = true) {
		if ($result) {
			$this->error = oci_error ( $this->queryID );
		} elseif (! $this->_linkID) {
			$this->error = oci_error ();
		} else {
			$this->error = oci_error ( $this->_linkID );
		}
		if ($this->debug && '' != $this->queryStr) {
			$this->error .= "\n [ SQL语句 ] : " . $this->queryStr;
		}
		return $this->error;
	}
	
	/**
     +----------------------------------------------------------
	 * SQL指令安全过滤
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param mix $str  SQL指令
     +----------------------------------------------------------
	 * @return string
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function escapeString($str) {
		return str_ireplace ( "'", "''", $str );
	}
	
	/**
     +----------------------------------------------------------
	 * 获取最后插入id ,仅适用于采用序列+触发器结合生成ID的方式
	 * 在config.php中指定
     'DB_TRIGGER_PREFIX'	=>	'tr_',
     'DB_SEQUENCE_PREFIX' =>	'ts_',
	 * eg:表 tb_user
     相对tb_user的序列为：
     -- Create sequence
     create sequence TS_USER
     minvalue 1
     maxvalue 999999999999999999999999999
     start with 1
     increment by 1
     nocache;
     相对tb_user,ts_user的触发器为：
     create or replace trigger TR_USER
     before insert on "TB_USER"
     for each row
     begin
     select "TS_USER".nextval into :NEW.ID from dual;
     end;
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return integer
     +----------------------------------------------------------
	 * @throws ThinkExecption
     +----------------------------------------------------------
	 */
	public function insertLastId() {
		if (empty ( $this->table )) {
			return 0;
		}
		$sequenceName = $this->table;
		$vo = $this->query ( "SELECT {$sequenceName}.currval currval FROM dual" );
		return $vo ? $vo [0] ["currval"] : 0;
	}
	
	/**
     +----------------------------------------------------------
	 * limit
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return string
     +----------------------------------------------------------
	 */
	public function parseLimit($limit) {
		$limitStr = '';
		if (! empty ( $limit )) {
			$limit = explode ( ',', $limit );
			if (count ( $limit ) > 1)
				$limitStr = "(numrow>" . $limit [0] . ") AND (numrow<=" . ($limit [0] + $limit [1]) . ")";
			else
				$limitStr = "(numrow>0 AND numrow<=" . $limit [0] . ")";
		}
		return $limitStr ? ' WHERE ' . $limitStr : '';
	}
}